Attached Link: Getting More Realistic Renders

You are sure to find some tips in the thread I've linked above. All kinds of rendering aspects are discussed in it : lighting, turning texture filter off etc etc. Many pages to read , so be warned !

" Try and be nice to people, avoid eating fat, read a good book every now and then, get some walking in, and try and live together in peace and harmony with people of all creeds and nations."
-Monty Python